# Relationship history for MSHA mine 1512213

Current hierarchy: **Cheek Kenneth & Gary--Chris Roberts → Cheek & Roberts Coal Company → No 1 Surface Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Cheek & Roberts Coal Company → No 1 Surface Mine; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cheek Kenneth & Gary--Chris Roberts → No 1 Surface Mine; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cheek Kenneth & Gary--Chris Roberts → Cheek & Roberts Coal Company; 1980-02-01 to current/open; source msha-controller-operator-history